Immunogenicity and protection efficacy of a COVID-19 DNA vaccine encoding spike protein with D614G mutation and optimization of large-scale DNA vaccine production.

Severe acute respiratory syndrome coronavirus 2 had devastating consequences for human health. Despite the introduction of several vaccines, COVID-19 continues to pose a serious health risk due to emerging variants of concern. DNA vaccines gained importance during the pandemic due to their advantages such as induction of both arms of immune response, rapid development, stability, and safety profiles. Here, we report the immunogenicity and protective efficacy of a DNA vaccine encoding spike protein with D614G mutation (named pcoSpikeD614G) and define a large-scale production process. According to the in vitro studies, pcoSpikeD614G expressed abundant spike protein in HEK293T cells. After the administration of pcoSpikeD614G to BALB/c mice through intramuscular (IM) route and intradermal route using an electroporation device (ID + EP), it induced high level of anti-S1 IgG and neutralizing antibodies (P < 0.0001), strong Th1-biased immune response as shown by IgG2a polarization (P < 0.01), increase in IFN-γ levels (P < 0.01), and increment in the ratio of IFN-γ secreting CD4+ (3.78-10.19%) and CD8+ (5.24-12.51%) T cells. Challenging K18-hACE2 transgenic mice showed that pcoSpikeD614G administered through IM and ID + EP routes conferred 90-100% protection and there was no sign of pneumonia. Subsequently, pcoSpikeD614G was evaluated as a promising DNA vaccine candidate and scale-up studies were performed. Accordingly, a large-scale production process was described, including a 36 h fermentation process of E. coli DH5α cells containing pcoSpikeD614G resulting in a wet cell weight of 242 g/L and a three-step chromatography for purification of the pcoSpikeD614G DNA vaccine.

Removal of textile dye, direct red 23, with glutaraldehyde cross-linked magnetic chitosan beads.

One of the most important classes of pollutants is dyes, and today there are more than 100,000 commercial dyes. Conventional treatment processes are very expensive, so it is essential to develop low-cost sorbent materials with high adsorption capacities. The aim of this study is to prepare magnetic microsized adsorbents that have high adsorption capacity for removal of direct red 23. Through this objective, glutaraldehyde cross-linked magnetic chitosan beads were formed in order to remove the textile dye direct red 23. Barium ferrite was used to give a magnetic property so that the beads could easily be separated from the water after treatment. The effects of barium ferrite, pH, incubation time, dye concentration, and glutaraldehyde amounts were investigated. The Langmuir and Freundlich adsorption models were applied to describe the equilibrium isotherms. The adsorption capacity had a very large value: 1250 mg/g at pH 4.0, at room temperature. Compared with activated carbon, magnetic cross-linked chitosan exhibits excellent performance in the adsorption of anionic dyes and the magnetic properties of beads enable us to remove the beads from the water after treatment. Pseudo-second-order and intraparticle diffusion kinetic models were applied.

An intravenous application of magnetic nanoparticles for osteomyelitis treatment: An efficient alternative.

The infection of bone and bone marrow is called osteomyelitis. Treatment is difficult since antibiotics can not reach with enough concentration to the infected area. For the first time in this study, we have developed gentamicin-loaded magnetic gelatin nanoparticles (GMGNPs) for nanocarrier-mediated and magnetically targeted osteomyelitis therapy. Gelatin, genipin, and magnetite were used for preparation of that novel carrier system due to their biodegradable and biocompatible properties. Cross-linking degree of gelatin nanoparticles, concentration of magnetite nanoparticles, and adsorbed drug amount were optimized. Furthermore, nanoparticles were characterized and the drug release profile was determined. The osteomyelitis model was constituted in the proximal tibia of rats. The therapeutic potential of GMGNPs on rats was monitored via X-Ray radiography and hematological and histopathological analyses were performed. According to the results, 110.3 ± 8.2 µg gentamicin/mg GMGNPs were used, hydrodynamic size was measured as 253.7 ± 11.8 nm, and GMGNPs have controlled drug release profile. Based on in vivo and ex vivo studies, after six doses of GMGNPs treatment, abscess began to heal and the integrity of periost and bone began to reconstruct. In conclusion, it can be suggested that GMGNPs could provide efficient therapy for osteomyelitis.

Development of Ultrasound-Triggered and Magnetic-Targeted Nanobubble System for Dual-Drug Delivery.

Non-small cell lung cancer (NSCLC) constitutes more than 85% of lung cancer case. Pemetrexed is used to treat types of NSCLC, and pazopanib is used for some types of soft tissue sarcoma. The aim of the study was development of pemetrexed and pazopanib carrying nanobubble system with magnetic responsiveness and ultrasound sensitivity properties for targeted NSCLC therapy. Drugs were linked to newly designed peptide, and peptide drug conjugates were attached to amine-modified magnetite. Resulting nanoparticles were encapsulated into liposomes, and liposomes were extruded, then nanobubble system was prepared. Moreover, nanobubble biodistribution was monitored by in vivo imaging system. As a result, based on high-performance liquid chromatography data, magnetite and peptide-pemetrexed were conjugated with 54.02% yield, and magnetite and peptide-pazopanib were bound with 63.53% yield. Hydrodynamic size of nanobubbles, prepared from liposomes filtered through 800 nm and 400 nm, was determined as 491.1 ± 130.2 and 275.8 ± 117.8 nm, respectively. Carrier system was accumulated into tumor area with 80.22% yield of the injected carrier system. It was found that nanobubbles were magnetic responsive for accumulation via magnetic field and could be disrupted by ultrasound via focused acoustic pressure, which lead to targeted drug delivery. These nanobubble systems could be investigated for intravenous and inhaler administration in further studies.

In vitro and in vivo evaluation of folate receptor-targeted a novel magnetic drug delivery system for ovarian cancer therapy.

Doxorubicin is widely used anticancer drug; however, use of doxorubicin is limited. Under externally applied magnetic field, magnetic agents can help to transport drug directly to tumor. Folate receptor is overexpressed in ovarian carcinomas. In this study, we aimed to develop magnetically responsive and folate receptor-targeted biomimetic drug delivery system for ovarian cancer therapy. Doxorubicin-loaded and glucose/gluconic acid-coated magnetic nanoparticles were synthesized and erythrocyte membrane vesicles were used for coating of nanoparticles. Folate ligand was anchored to surface so as to target receptor. Hydrodynamic size of nanocarrier was found as 91.2 ± 20.8 nm. The results showed that delivery system has controlled drug release profile and biocompatible features. In folate-free medium, folate receptor-targeted nanocarrier showed 10.33-fold lower IC50 values for A2780 cells and 3.93-fold lower for OVCAR3 cells compared to non-targeted nanoparticles and demonstrated more cytotoxicity against ovarian cancer cells. Moreover, magnetically and folate receptor-targeted doxorubicin delivery system was significantly more effective for therapy of xenografted nude mice than free doxorubicin based on tumor shrinkages and biochemical parameters. In conclusion, it can be suggested that folate ligand-attached and biomimetically designed magnetic drug delivery system have advantages and potential for targeted ovarian cancer therapy.

A novel second-generation platinum derivative and evaluation of its anti-cancer potential

Abstract Cisplatin is the primary anti-cancer agent for the treatment of most solid tumors. However, platinum-based anti-cancer chemotherapy produces severe side effects due to its poor specificity. There are a broad interest and literature base for a novel mechanism of action on platinum derivatives. Additionally, combining cisplatin with histone deacetylase inhibitors (HDACi) such as 4-hydroxybenzoic acid derivatives showed promising results in treating solid tumors. Here we aimed to conjugate 4-hydroxybenzoic acid with platinum to obtain a novel platinum derivative that can overcome cisplatin resistance. Cis-4-hydroxyphenylplatinum(II)diamine compound was synthesized under mild conditions and characterized. Cytotoxicity assay was performed on SKOV3-Luc and A549-Luc cells. Hemocompatibility and serum protein binding analysis were performed. Treatment potential was evaluated in xenograft tumor models. Biodistribution was tested on tumor-bearing mice via Pt analysis in organs with ICP-MS, ex vivo. In this study, cis-4-hydroxyphenylplatinum (II) diamine was synthesized with a yield of 62%. The MTT assay on A549-Luc and SKOV3-Luc cell lines resulted in IC50 values of 17.82 and 7.81 µM, respectively. While tumor growth was continued in the control group, the tumor volume decreased in the treatment group. All results point to the conclusion that the new compound has the potential to treat solid tumors

Development of gemcitabine-adsorbed magnetic gelatin nanoparticles for targeted drug delivery in lung cancer.

Magnetic iron oxide nanoparticles (IONPs) were coated with gelatin type B by means of the two-step desolvation method. Drug loading by adsorption was studied under various conditions such as different temperature, contact time, pH, and initial gemcitabine concentration. Further, Langmuir isotherm curves were constracted and constants were calculated. According to the Langmuir isotherm, the Gibbs free energy of the adsorption process at 25°C was - 4.74 kJ/mol. On the other hand, this value at 37°C was - 7.86 kJ/mol. In vitro drug release was performed at pH levels of 5 and 7.4, with gemcitabine-loaded magnetic gelatin nanoparticles and free gemcitabine, and both the results were subsequently compared.

In vitro evaluation of doxorubicin-incorporated magnetic albumin nanospheres.

Magnetic albumin nanospheres that incorporate doxorubicin (M-DOX-BSA-NPs) were prepared previously by our research group to develop magnetically responsive drug carrier system. This nanocarrier was synthesized as a drug delivery system for targeted chemotherapy. In this work, cytotoxic effects of doxorubicin (DOX)-loaded/unloaded or magnetic/non-magnetic nanoparticles and free DOX against PC-3 cells and A549 cells were determined with the MTT test and the results were compared with each other. DOX-loaded magnetic albumin nanospheres (M-DOX-BSA-NPs) were found more cytotoxic than other formulations. The quantitative data obtained from flow cytometry analysis further verified the higher targeting and killing ability of M-DOX-BSA-NPs than free DOX on both of the cancer cell lines. Additionally, the results of cell cycle analysis have showed that M-DOX-BSA-NPs affected G1 and G2 phases. Finally, cell images were obtained using spin-disk confocal microscopy, and cellular uptake of M-DOX-BSA-NPs was visualized. The findings of this study suggest that M-DOX-BSA-NPs represent a potential doxorubicin delivery system for targeted drug transport into prostate and lung cancer cells.

Preparation of magnetic gelatin nanoparticles and investigating the possible use as chemotherapeutic agent.

Iron oxide nanoparticles coated with gelatin trough two-step desolvation method and characterized. SEM analyse showed that the nanoparticles are spherical and TEM image showed that the iron oxide nanoparticles encapsulated with gelatin. Also FTIR, TG and magnetization analyses exhibited that iron oxide nanoparticles encapsulated as well. Drug loading by adsorption studied under various conditions as different temperature, contact time and initial cisplatin concentration. Also, Langmuir, Freundlich and Dubinin-Raduskevich adsorption isotherm curves were constracted and constants were calculated. In vitro drug release was performed at pH 5 and 7.4 and hyperthermic drug release investigated at 42°C and compared with non-hyperthermic drug release.